Fuse switch



NOV. 10, 1936. c AT H ET AL 2,060,514

j'FUSE SWITCH Filed April 29, 1955 3 Sheets-Sheet 1 Nav. 10, 1936.

c. L. MATTHEWS ET AL FUSE SWITCH 5 Sheets-Sheet 2 Filed April 29, 1955 Nov. 10, 1936. c. L. MATTHEWS ET AL 2,060,514

FUSE SWITCH Filed April 29, 1935 3 Sheets-Sheet 3 Patented Nov. 10, 1936 UNITED STATES PATENT OFFICE.

FUSE SWITCH Missouri Application April 29, 1935, Serial No. 18,834

25 Claims.

This invention relates to fuse switches, and with regard to certain more specific features, to gang-operated fuse switches.

Among the several objects of the invention may be noted the provision of a fuse switch having a fusible element adapted to open a circuit upon overload by actually fusing and blowing out, and adapted to open the same circuit by moving out of circuit-closing position'when the carrier therefor is moved out of circuit-closing position; the provision of apparatus of the class described which is adapted to effectively open a multi-phase circuit instantaneously and positively in all of the phases, from a single manually operable remotely-controlled element; and the provision of relatively simple and dependable apparatus of this class. Other objects will be in part obvious and in part pointed out hereinafter.

The invention is an improvement upon that shown in our United States Patent 1,899,915 of February 28, 1933.

The invention accordingly comprises the elements and combinations of elements, features of construction, and arrangements of parts which will be exemplified in the structures hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings, in which is illustrated one of various possible embodiments of the invention,

Fig. 1 is a side elevation on a reduced scale showing parts in closed position;

Fig. 2 is a view similar to Fig. 1, showing parts in open position;

Fig. 3 is an enlarged fragmentary side elevation of a lower contact assembly;

.Fig. 4 is a front elevation, showing a plurality of fuse switches in closed positions;

Fig. 5 is a side elevation of a fuse unit per se,

parts being shown in section;

Fig. 6 is a vertical section taken on line H of Fig. 3; and,

Fig. "l is a horizontal section taken on line |-'l of Fig. 3.

Similar reference characters indicate corresponding parts throughout the several views of the drawings.

One of the purposes of this invention, besides providing for improved gang-operation of fuse 5o switches, is to provide an improved fuse switch per se in which a fuse unit may set to close a circuit through a fusible link, the link opening the circuit upon overload by actual fusion thereof; and also opening the circuit upon movement 55 of the unit to prevent undesirable arcing between certain terminal-engaging elements on the unit and certain line terminals in the circuit. The present fuse switch retains all of the desirable characteristics inherent in actual fusing a link for disconnecting overload, with the other auto- 5 maticopening features herein described.

Referring now more particularly to Fig. 4, there are shown at numerals I supports for carrying upper, stationary, insulator brackets 3 carrying insulators 5 for supporting brackets 53 which 10 carry spring line terminals 1 and line connections 55 (see also Fig. 1).

Downwardly, each support I carries a pair of bearing blocks 9 for rotatably supporting a gangoperating shaft ll. Within the bearing blocks 9, 15 the shaft II is circular so that it may rotate in said blocks, and suitable collars I3 are provided for properly positioning the shaft endwise.

Outside of thebearings 9, the shaft II is of a polygonal (preferably square) cross section, 20 whereby operating and operated members may be readily fastened. The shaft ll may be operated from a remote point through the provision of a clevised lever l5 clamped to the shaft and connected with a swinging link II by means of a 25 connecting rod IS. The link I! is pinned to a bracket 33. At the vpivot point 2| between the links I! and I9 is also fastened a second connecting link 23 which is articulated at a pin 25 with an operating handle 21, the latter being 30 pinned at 29 to a bracket 3|.

The operating lever 21 has an extension 35 wherein is an opening 31 which is adapted to align with a downward opening in the bracket 3| when the handle 21 is in the upward position 5 shown in Fig. 1. Both openings may be entered by a bolt 23 to lock the linkage and connected parts in the closed Fig. 1 position. 0n the other hand, when the handle 21 is down in the position shsown in Fig. 2, said opening 31 aligns 40 with a second, upper opening in the bracket 3|, thus providing for the insertion of the bolt 23 at this point to lock the apparatus in open position. The extension 35 oflever 21 can move from the position shown in Fig. 1 to the position 45 shown in Fig.2 by movement through a slot 32 in the bracket 3i. A corresponding slot is arranged in whatever supports the bracket 3i.

Extending from one of each pair of said bearings 3 (the left-hand ones in each pair in Fig. 4) is a stationary extension 4| for supporting a fixed insulator 43, the latter carrying a bracket 49 which supports spring contacts 45. A line connection 41 is attached to the bracket 49.

In view of the above, it will be seen that two 56 line terminals 48 and 1 are provided, both be-- ing stationary.

As stated, the bearings 8 are in pairs. At the left of each right-hand bearing 8 of each'pair (Fig. 4), and clamped to the squareportion of said shaft II is an arm 51 supporting a tilting insulator 44. From each insulator 44 extends. a bracket 58 reaching in the direction of the arm 48 and carrying a socket 58. The socket has side walls 5| in which are formed channels having the double notched shapes shown in Fig. 3. The purpose of the socket 58 with the notched, side channels 88 is to receive longitudinally a lower terminal-engaging element fastened to a fuse tube 81 having latch means 88 arranged to coact with the channels 88. Spurs H in the bayonet latches 88 are respectively adapted to cooperate with notches 18 in said channels 88 when the respective tube 81 with its terminal-engaging elements 85 is rocked or moved to the left or right. The terminalengaging element 85 has a flat surface 18 engageable by means of the spring fingers 45 when the 'fuse is in the closed position shown in Figs. 1 and 3. The element 85 is shown forced to the right in Fig. 3 by the reaction of springs 45. In a neutral position, the latch 58 may be adjusted so that its spurs 1| clear the notches 18 so that the tube 81 may be lifted with the terminal-engaging element 65 to clear the socket 58. A shoulder 15 resting against the back 11 of the socket 58 properly positions the spursll below the notches 18 when the tube 61 is in socketed position.

The fuse unit per se is described in our said United States Patent 1,899,915. It includes a leaf spring 8| attached to said terminal-engaging element 85 and normally tensioned by the pull of a fuse link 88 which is clamped to the spring 8| by means of a lever 85, said lever 85 being pivoted at 85 to the spring 8| and clamp- I ing the link 88 at 81, the pulled fuse link 88 being looped over its end.

The link 88 enters the lower, open end of the tube 81 and is held at the upper end in an upper metallic terminal-engaging element 88, which engages with the spring line terminal 1. This terminal-engaging element 88 carries a slidable stem 88 for controlling an anvil 8|, the latter cooperating with'a removable anvil 88 on a thumb screw 85. A spring 81 normally presses theanvil 8| toward the anvil 88 to clamp the upper end of thelink 88. A stop 88 limits the movement of the anvil 8| to the right so that when the thumb screw 85 is loosened to permit entry of the link 88 between the anvils, the anvil 8| will not follow the anvil 88 except for a limited distance.

Stem 88 extends exteriorly of the hollow engaging element 88 and is pinned to a lever I8I, said lever in turn being pinned to an extension I88 forming a stop portion of said terminal-engaging element 88.

The bracket 58 carries an overhanging arm I85 over which is a sleet hood I81- A depending latch I88 is pivoted at III to said arm I85. The latch I88 has only a limited downward gravitational motion and free upward movement. Its sloping surface II8 when engaged by the lever I8l, permits free-moving of thefuse assembly into circuit-closing position and its vertical face "5 prevents free opening and causes, in connection with the lever I8I, fuse releasing functions.

As many of the units supported on frames I may be used, in connection with a given control shaft II, as may be desirable. In Fig. 4, two units are shown controlled by a single control shaft and an associated linkage operated from a single lever 21. For instance, a controlled unit may be used in each phase of a circuit.

The operation of the device is as follows:

Assuming that the fuse switch is closed, as shown in Figs. 1, 3, and 4, one or more of the fusible links 88 may fuse, due to overload or the like. This automatically effects blowing of the respective fuse to extinguish the resulting arc interiorly of the respective tube 81. This releases the spring 8| and lever 85 pivoted thereto so that the unburned portion of the link is pulled out and it is dropped as it is pulled out by opening action at 81.

On the other hand, it may be desirable to open the circuit before any overload or short circuit has occurred. To do this the handle 21 is moved down, thus rotating the gang-controlled shaft I I and rotating each one of the insulators 44 and associated arms 51. Inasmuch as the sockets 58 on the arms 51 carry the fuse tubes 81, said tubes 61 are rotated clockwise (Fig. 2). This causes a separation between the terminal-engaging elements 88 and 55 from the line terminals 1 and 45 respectively. However, before separating movements can proceed to a condition of complete separation, the levers |8| strike the gravity latches I88, thus pulling the pins 88 so that the movable anvils 8| recede from the anvils 88, thus releasing the links 88 at their upper ends, whereupon they are pulled out of the respective tubes 81 by the respective springs 8|. If any arcs are formed, the rapid travel of the link away from the anvils causes substantially instantaneous extinguishment. After the electric circuit has been opened in the manner described, the respective terminal-engaging elements 88 and 85 completely break away from the line terminals 1 and 45, so that the, tubes are mechanically entirely out of the circuit and are safe for removal for fuse link renewal. In coming to a final open position, one of the spurs 1| positively comes in behind a notch 18 so that the tube will not drop from the remainder of the apparatus. Thereafter a lineman may grip the tube, and adjust it so that the spurs 1| clear the notches 18 and it may be removed for refusing by turning out the wing screw 85 and fastening in a new link 88 in between the anvils 8| and 88 and then fastening it to the spring 8|, at the same time tensioning the latter.

After all the tubes are re-fused, the tube units are reinserted into the sockets 58, the lever 21 is moved into its up position, thus sending all of the tubes counter-clockwise (Figs. 1 and 3). In closing the terminal-engaging elements 88 and 85 against the line contacts 1 and 45, respectively, the levers |8| slide under the gravity latches I88, temporarily lifting the same. Finally the stops I88 contact suitable portions of the brackets 58 so as to effect proper final positioning. It will be noted that as each tube 81 is driven to contact position, that a reaction is placed thereon by the spring contacts 45, so that the right-hand spur 1| is positioned under the right-hand notch 18 (Fig. 3). 'Hence if the fuse blows, the action engendered thereby will not project it up into contact with the arm I88.

It will be seen that among the advantages of the constructions is the fact that a circuit opening may be accomplished by manual means with- 75 out the danger of an open are between terminalengaging elements and the line terminals. Any arcing is confined to a position within the upper terminal-engaging elements and to the upper end of the downwardly moving link and is soon extinguished within the respective tube 61. At the same time overloads are disconnected by actual fusing of the fuse links, rather than by the less desirable process of pulling them outof contact.

The device provides means for instantaneously disconnecting one, two, three or 'more phases of an electrical circuit by the operation of a single band member at a distance from the point or points of connection of the respective fuses in the circuit.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As many changes could be made in carrying out the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

We claim:

1. A fuse switch comprising a support, line terminals thereon, an expulsive fuse tube assembly having terminal-engaging elements, means for moving said tube assembly to engage and disengage said elements and terminals, a fuse tensioned and electrically connecting said terminal-engaging elements, and cooperating means between the tube assembly and the support for automatically releasing said fuse from one of said elements in response to movement of said terminal-engaging elements in a direction from said line terminals.

2. A fuse switch comprising a plurality of pairs of line terminals, expulsive fuse tubes having each a pair of terminal-engaging elements, means for simultaneously moving said tubes so as to engage and disengage said pairs of elements and terminals, fuses respectively electrically connecting the members of said pairs of terminal-engaging elements, and means for automatically removing each of said fuses from at least one of said respective terminal-engaging elements in response to movement of said ter- -minal-engaging elements from said line ternunals.

3. A fuse switch comprising a plurality of pairs of line terminals, expulsive fuse tubes having each a pair of terminal-engaging elements,

means for simultaneously moving said tubes so as to engage and disengage said pairs of elements and terminals, fuses respectively electrically connecting the members of said pairs of terminal-engaging elements, and means for automatically and substantially simultaneously removing each of said fuses from at least one of said respective terminal-engaging elements in response to movement of said terminal-engaging elements from said line terminals, said means for moving all tubes being manually operable from a single remote point.

4. In a fuse switch, line terminals, a fuse unit having terminal-engaging elements, means for moving said fuse unit so that said terminal-engaging elements move into and out of contact with said terminal-engaging elements, a fuse connecting the terminal-engaging elements of said fuse unit, and means for automatically ,disconnecting said fuse from at least one of said terminal-engaging elements when said fuse unit is moved so as to effect disconnection between the terminal-engaging elements and the line terminals.

5. A fuse switch comprising a plurality of pairs of line terminals, a plurality of fuse units, each fuse having at least one pair of terminalengaging elements, means for simultaneously moving said fuse units so that said pairs of terminal-engaging elements move into and out of contact with the respective pairs of line terminals, fuse links in said" fuse units, and means for automatically and substantially simultaneously disconnecting each fuse from at least one terminal-engaging element in response to movements of the fuse units to disconnecting positions.

6. A fuse switch comprising fixed line terminals, a fuse unit comprising an expulsion tube, terminal-engaging elements associated with the tube, means for mounting said tube to move said terminal-engaging elements into and out of contact with respect to said line terminals, a link in said tube, means biasing said link to tension the same and tend to withdraw it from the tube, means for retaining said link in the tube against said bias, said link electrically connecting said terminal-engaging elements, and means contacting said retaining means for automatically releasing said retaining means in response to movement of the tube to disconnect the terminal-engaging elements from the line terminals. '7. A fuse switch comprising fixed line terminals, a fuse unit comprising an expulsion tube having an opening at the lower end, terminalengaging elements associated therewith, means for removably mounting said tube to move said terminal-engaging elements into and out of contact with respect to said line terminals, a link extending out of the opening of said tube, means exteriorly of the tube biasing said link to tension the same and tend to withdraw it from the tube, means for retaining said link in the tube against said bias, said link electrically connecting 'said terminal-engaging elements, means contacting said retaining means for automatically releasing said retaining means in response to movement of the tube to disconnect the terminal-engaging elements from the line terminals, whereby the link is drawn from the tube and projected from said opening, and means for completely disconnecting the link from the apparatus as it is projected.

8. A fuse switch comprising fixed line terminals, a movable carrier associated with one of said terminals, an expulsion fuse tube adapted to be attached to and removed from said carrier, terminal-engaging elements on said tube, said carrier being movable to carry said terminal-engaging elements into and out of contact with said line terminals, a link electrically connecting said terminal-engaging elements, means biasing said link away from one of said terminal-engaging elements, means adapted to hold said link against movement by said biasing means, and automatic means for releasing said link to be separated from one terminal-engaging element in response to carrier movement in a direction to separate said terminal-engaging elements and said line terminals, but before said engaging elements and terminals are electrically separated, whereby the electrical circuit is opened before the terminalengaging elements and line terminals are separated. v

9. A fuse switch comprising fixed line terminals, a movable carrier associated with one of rate said terminal-engaging elements and said line terminals, said automatic means comprising spring-pressed means holding the link, a latch, and means associated with said spring-pressed means whereby upon movement of the tube to circuit-closing position, said spring-pressed means is undisturbed and whereby upon movement of said tube toward open-circuit position, said latch efiects operation of said spring-pressed means to release the fuse link.

10. In a fuse switch, line terminals, terminalengaging elements adapted to be engaged and disengaged therewith, a tube joining said terminal-engaging elements to form a cartridge, a fuse link electrically connecting said terminal-engaging elements and within said tube, means for tensioning said link and means for automatically throwing said link out of electrical connection with at least one terminal-engaging element, in response to disengagement of the terminal-engaging elements from the line terminals.

11. In a fuse switch, line terminals, terminalengaging elements adapted to be engaged and disengaged therewith, a fuse unit joining said terminal-engaging elements, a fuse link electrically connecting said terminal-engaging elements and in said unit, and means for automatically disconnecting said link from the terminal-engaging elements in response to the terminal-engaging elements moving toward disengagement from the line terminals.

12. A fuse switch comprising terminal-engag ing elements, enclosure means carrying said elements, a fuse link connecting said elements and in said enclosure means, means for releasing said link from one of said elements, line. terminals and means for contacting the terminal-engaging elements therein, and means automatically operable for releasing the link in response to said terminal-engaging elements moving from contact with the line terminals.

13. A fuse unit for closing electrical circuits comprising circuit terminal-engaging elements, a fuse link connecting said elements, and means for automatically disconnecting said link from one of said elements in response to removal of the cartridge from circuit-closing condition.

14. A fuse unit for closing electrical circuits comprising circuit terminal-engaging elements, a fuse link connecting said elements, means for tensioning said link, and means for automatically releasing said link from one of said elements in response to cartridge removal from operating condition and before it is entirely removed.

15. A fuse switch comprising line terminals, terminal-engaging elements, a fuse link connecting said elements, means for tensioning said link between elements, means for releasing said link iromone of said elements while the cartridge is in operating condition, said last-named means comprising a spring-pressed clamp for holding one end of said link, a tensioning means for said link, and automatic means for releasing the 'link against withdrawal, said last-named means comprising a movable anvil, spring-pressed means adapted to be forced toward said anvil to hold the end of the link, line terminals, means for moving said terminal-engaging elements into and out of contact with line terminals, and means for automatically moving said springpressed means away from said anvil to release the link in response to movement of the tube in a direction to disconnect said terminal-engaging elements from said line terminals.

17. In apparatus of the class described, a cartridge having a closed head, a link, means for holding said link in said closed head, said lastnamed means comprising an anvil, resilient means clamping said link against said anvil, automatic means exteriorly operable for releasing the automatic hold on said link, means for moving the cartridge into and out of said circuit-closing position, said automatic means being operable for release only when said cartridge is moved in the direction of its open-circuit position.

18. A switch comprising line terminals, terminal-engaging elements, conducting means con necting said elements, means for tensioning said conducting means and means for automatically releasing the conducting means from one of said terminal-engaging elements, said automatic means being effective only when the terminalengaging elements are moved in a direction away from said line terminal.

19. A switch comprising line terminals, terminal-engaging elements, an enclosure having at least one opening and upon which said engaging elements are mounted, a conductor joining said engaging elements and positioned in said enclosure, means tensioning the conductor and means for automatically releasing the conductor while electrified from one of the engaging elements when the terminal-engaging elements are moved in a direction to separate them from the line terminals.

20. A fuse switch comprising terminal-engaging elements, means joining said elements forming an enclosure, a fuse link in said enclosure and joining said elements, whereby a movable fuse unit is formed, line terminals, means mounting said fuse unit for moving said terminalengaging elements into and out of contact with the line terminals, means for maintaining a connection between the link and the terminal-engaging elements when the unit is moved to contact the terminal-engaging elements with the line terminals but automatically to disconnect the link from at least one terminal-engaging element in response to separation of the terminalengaging elements from the line terminals, whereby after circuit closure, the circuit can only be reopened by way of said fuse link either by blowing of the link or by initial movement of fuse unit.

21. A fuse switch comprising line terminals, terminal-engaging elements, means for moving said terminal-engaging elements into and out of contact with the line terminals, a fusible link electrically joining said terminal-engaging elements, means for electrically disconnecting said link from said engaging elements in response to movement of the engaging elements away from the line terminals but permitting the link to fuse upon overload without separation of the engaging elements from the line terminals.

22. A fuse switch comprising a plurality of pairs of line terminals, a plurality of pairs of corresponding terminal-engaging elements, means for moving said pairs of terminal-engaging elements into and out of contact with the respective pairs of line terminals, fusible links respectively electrically joining the members of said pairs of terminal-engaging elements, means for substantially simultaneously electrically disconnecting all of said links from said engaging elements in response to movement of the engaging elements away from the line terminals but permitting the links to fuse upon overload without separation of the engaging elements from the line terminals.

23. A fuse switch comprising line terminals, a pivoted socket, an expulsion fuse cartridge including means applicable into said socket and portions engageable with said line terminals, and locking means between the means in the socket and said socket adapted automatically to look upon movement of said portions into engagement with the line terminals, but to readily unlock under manipulations adapted to remove the said means from the socket.

24. A fuse switch comprising line terminals, one of which is resilient, a pivoted socket, an expulsion fuse cartridge including terminal engaging elements, part of said cartridge being applicable to said socket, and locking means between the part of the cartridge in the socket and said socket adapted automatically to look upon contact between the terminal engaging elements and the line terminals, but to readily unlock under manipulations adapted to remove the cartridge from the socket.

25. A fuse switch comprising line terminals one of which is resilient, a pivoted socket electrically associated with the resilient terminal, an expulsion fuse cartridge including terminal engaging elements, one of said terminal engaging elements being applicable to said resilient socket, and locking means between the terminal engaging element in the socket and said socket adapted automatically to lock upon movement of the socket toward the resilient terminal and upon contact between the terminal engaging element in the socket and the resilient line terminal, but to readily unlock under manipulations adapted to remove the cartridge from the socket when the socket is moved away from the resilient terminal.

CLAUD L. MA'I'I'HEWS. THEODORE BIRKENMAIER. 

